This is a Phase II study to look at the effects of the investigational drug DMP 754 which has potential potent effects on platelet aggregation. This protocol consisted of eight parts, of which we participated in four. DMP 754 was studied in the following doses: 0.25 mg, 0.5 mg, 0.75 mg, 1.0 mg, 1.25 mg, 1.5 mg, 2.0 mg or 2.5 mg daily for up to 30 days. Endpoints include tolerability and safety and also effectiveness in inhibiting platelets as assessed by platelet aggregation studies.